perl Makefile.PL # Maybe some option here? os=all|Linux|AIX|RHEL|Suse
make             # To get everything or things covered with option
                 # And if option is not possible:
make Linux       # To get Base plus all Linux stuff
make RHEL        # To get Base plus Linux.pm plus RHEL.pm
make Suse        # To get Base plus Linux.pm plus Suse.pm
make AIX         # To get Base plus AIX.pm
make test        # To test all related tests
make install     # To install only selected modules

##</code><code>##

CONFIGURE

    CODE reference. The subroutine should return a hash
    reference. The hash may contain further attributes,
    e.g. {LIBS => ...}, that have to be determined by some
    evaluation method.

##</code><code>##

sub MY::postamble {
    return <<'MAKE_FRAG';
    $(MYEXTLIB): sdbm/Makefile
    cd sdbm && $(MAKE) all
    MAKE_FRAG
}